Mutations in the MFN2 (mitofusin 2) and OPA1 genes, both involved in mitochondrial transport and/or fusion, cause two hereditary neurodegenerative disorders, respectively an axonal peripheral neuropathy (Charcot-Marie-Tooth Type 2, CMT2) and the dominant optic atrophy (DOA) [73]. Here, OPA1 is linked to autosomal dominant optic atrophy.